We study dissociative electron attachment to furan (FN) $\left({\mathrm{C}}_4{\mathrm{H}}_4\mathrm{O}\right)$ , tetrahydrofuran (THF) $\left({\mathrm{C}}_4{\mathrm{H}}_8\mathrm{O}\right)$ , and fructose (FRU) $\left({\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\right)$ using crossed electron/molecular beams experiments with mass spectrometric detection of the anions. We find that FN and THF are weak electron scavengers and subjected to dissociative electron attachment essentially in the energy range above $5.5\mathrm{eV}$ via core excited resonances. In striking contrast to that, FRU is very sensitive towards low energy electrons generating a variety of fragment ions via a pronounced low energy feature close to $0\mathrm{eV}$ . These reactions are associated with the degradation of the ring structure and demonstrate that THF cannot be used as surrogate to model deoxyribose in DNA with respect to the attack of electrons at subexcitation energies $(<3\mathrm{eV})$ . The results support the picture that in DNA the sugar moiety itself is an active part in the initial molecular processes leading to single strand breaks.

DNA origami technology allows for the precise nanoscale assembly of chemical entities that give rise to sophisticated functional materials. We have created a versatile DNA origami nanofork antenna (DONA) by assembling Au or Ag nanoparticle dimers with different gap sizes down to 1.17 nm, enabling signal enhancements in surface-enhanced Raman scattering (SERS) of up to 10¹¹. This allows for single-molecule SERS measurements, which can even be performed with larger gap sizes to accommodate differently sized molecules, at various excitation wavelengths. A general scheme is presented to place single analyte molecules into the SERS hot spots using the DNA origami structure exploiting covalent and noncovalent coupling schemes. By using Au and Ag dimers, single-molecule SERS measurements of three dyes and cytochrome c and horseradish peroxidase proteins are demonstrated even under nonresonant excitation conditions, thus providing long photostability during time-series measurement and enabling optical monitoring of single molecules.

DNA origami nanostructures are used to arrange gold nanoparticles into dimers with defined distance, which can be exploited as novel substrates for surface enhanced Raman scattering (SERS). Single dye molecules (TAMRA and Cy3) can be placed into the SERS hot spots, with Raman enhancement up to 10¹⁰, which is sufficient to detect single molecules by Raman scattering.